There are more and more devices that are battery-powered and which have high power consumptions. Efforts are being made to either improve the performance of the battery or reduce the power consumption of the devices. Mobile phones are one such portable battery-powered devices where lower power design strategies are needed to save energy and maximize battery life.
Video cameras in battery-powered applications remain a relatively new area to this problem, and thus traditional approaches to reducing active power have been generally applied. Recently, efforts have been made in the design and manufacture of semiconductors for these applications in order to make them more power efficient.
In one such example, deep sub-micron CMOS silicon processes provide reduced voltage (V) in an effort to positively impact the power equation (CV2f)/2, where C is capacitance, V is voltage and f is frequency. The voltage V is a dominant factor. In another example, digital IC design CAD vendors provide automatic clock gating tools to tackle instantaneous power issues by introducing heavily loaded, capacitive clock-trees.
Generally, in system design the frequency component of operation is somewhat constrained by the system specification but can, in some applications, be reduced resulting in an approximately linear reduction in active power.
These examples provide some improvements but do not generally go far enough for the high expectations with respect to power efficiency with these types of devices. Also, maximizing image performance and battery life continue to be significant product differentiating features in portable, battery-powered camera markets.